Field of the Invention
Hair care products morphology.
From a morphological point of the view the hair shaft consists of elongated keratinizing cells which are cemented together and known collectively as the "cortex."
The cortex is surrounded by an external cuticle which arises from a single line of cells in the bulb of the hair shaft. Eventually the cuticle evolves into five to ten overlapping layers forming an external barrier. When viewed externally, the cuticle scales appear imbricated, similar to the placement of roof tiles, with free edges directed outwardly, thus forming a barrier preventing the free passage of hair care agents.
Hair is composed of an insoluble protein material called keratin, which is formed as the ultimate product of the keratinization process which occurs in the hair follicle. In addition, small quantities of water soluble substances such as pentose sugars, phenols, uric acid, glycogen and glutamic acid, are also present.
As a result of chemical bonding, hair assumes a cross-linked structure depicted as submicroscopic fibrils containing both parallel and linked polypeptide chains. The fibrils are relatively impervious to penetration by outside agents especially in the crystalline regions and is known as the alpha-keratin structure with a helical arrangement. Although this crystalline structure shows a pronounced degree of regularity, it is not to be regarded as crystalline in the sense that it is associated with inorganic materials. Furthermore, it has been determined that the helical structure possesses a more refined internal structure that is also helical in nature. Therefore, there is a helix within a helix. The more closely packed regions of protofibrils contain structures in which six of these screw-shaped helices have twisted about another so as to form a compound helix. This structure resembles a seven-stranded cable as shown in FIG. 1. The cable-like structure is representative of the crystalline regions of alpha keratin.
In addition, these amorphous regions are not protected from outside attack by the structural side chains of the compound helix. However, these amorphous regions do offer a partial barrier allowing the passage of some materials but not others.
Hair has very many characteristics differing from person to person. One of the very common characteristics is dry, brittle hair shafts which break off easily and leave an uneven and unattractive hair appearance. There are many products available on the open market for coating hair to form a softer appearance with a pleasant sheen. However, such products do not possess the carrier potential that is found in the HS-GL carrier system.
It is an object of this invention to penetrate both the crystalline and amorphous hair structure with a character modification chemical.
Specifically, it is an object of this invention to enable a liposome coated with a modified lecithin such as glycerine to penetrate the hair shaft and induce improved character of the hair shaft.
It is a further object of this invention to penetrate the cuticle sheath of a hair structure by a carrier that will transport a humectant into the interior structure of hair to lubricate and humidify the structure of the hair helix.
A still further object of this invention is to provide a modified form of lecithin that will penetrate the fibrils of a hair shaft with a surface modification of glycerin which facilitates penetration of the hair shaft with glycerin and other humectants.
Also, it is an object of this invention to provide improved means for inducing a desired color to hair shafts.
Furthermore it is an object of this invention to provide a modified form of lecithin that will act as a carrier for therapeutic and cosmetic agents.